Fayaz A. Khan,Humna Hamid,Yasir I. Badrashi,



CFD,High Resolution,Shock Capturing,Mobile Beds,


With the advances in the field of computing, robust CFD models have evolved in the last two decades. Initially, one and two-dimensional models were used but these days, three-dimensional models are used frequently that produce more accurate results. However, the solution of 3D models is expensive not only in terms of computational costs but is time-consuming. In this work, a two-dimensional CFD model that is based on shallow water equations coupled with an erosion model is presented. The equations are solved using finite volume formulation and high-resolution shock capturing methods. This study is an attempt to cover accuracy issues with 2D models by incorporating high-resolution shock capturing methods as compared to 3D models, the solution of which is based on conventional schemes. The model is initially used to simulate dam-break problems over fixed and mobile beds to assess the model stability and hydraulic performance in terms of simulating the flow and bed morphology. The assessment has shown the model to be stable throughout the simulation and the produced results have shown the hydro-dynamic capability of the model. The model is then applied to simulate flow over an erodible sediment bed in a channel with spur dykes on its flood plain. The simulated results are compared with experimental results and numerical results of a 3D model. The comparison has shown a close agreement both with experimental and numerical 3D model results that show that the model could be applied to study bed morphology confidently.


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